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01-01-2010 | Brief Report

Identification and functional analysis of novel BRCA1 transcripts, including mouse Brca1-Iris and human pseudo-BRCA1

Authors: Christopher A. Pettigrew, Juliet D. French, Jodi M. Saunus, Stacey L. Edwards, Aisha V. Sauer, Chanel E. Smart, Therese Lundström, Christiane Wiesner, Amanda B. Spurdle, Joseph A. Rothnagel, Melissa A. Brown

Published in: Breast Cancer Research and Treatment | Issue 1/2010

Abstract

Recent characterization of the mammalian transcriptome has confirmed its predicted complexity, with many loci encoding multiple splice variants and pseudogenes. The breast cancer susceptibility gene BRCA1 is a tumour suppressor gene that produces multiple functional transcripts. For example, BRCA1-IRIS is a splice variant of BRCA1, which encodes a protein that is functionally distinct from BRCA1. Here we describe the identification of ten novel Brca1 splice variants including Brca1-Iris, the mouse orthologue of human BRCA1-IRIS. We show that Brca1-Iris is differentially expressed during mammary epithelial differentiation and regulates survival of mammary epithelial cells. Another transcript, Brca1-Δ22, expressed in both mouse and human cells, was found to be defective in transcriptional activation capacity. Finally, we show that the human BRCA1 pseudogene produces a spliced pseudoBRCA1 transcript. The identification of these transcripts has implications for the understanding of the role of BRCA1 in biology and disease and for the interpretation of mouse knockout models.

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Title: Identification and functional analysis of novel BRCA1 transcripts, including mouse Brca1-Iris and human pseudo-BRCA1
Authors: Christopher A. Pettigrew
Juliet D. French
Jodi M. Saunus
Stacey L. Edwards
Aisha V. Sauer
Chanel E. Smart
Therese Lundström
Christiane Wiesner
Amanda B. Spurdle
Joseph A. Rothnagel
Melissa A. Brown
Publication date: 01-01-2010
Publisher: Springer US
Published in: Breast Cancer Research and Treatment / Issue 1/2010
Print ISSN: 0167-6806
Electronic ISSN: 1573-7217
DOI: https://doi.org/10.1007/s10549-008-0256-2

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